Effects Of Different Environment And Processing Conditions On The Growth And Nutrient Components Of Phaeophyta

Phaeophyta have wide application value in industry,medicine,culture and so on.Because of the development of human economy and expand the scale of farming,uncontrolled exploit of the Phaeophyta resources by human beings,cause environmental damage and the Sargassum field is degraded and disappearing.This article thoroughly studied effects of different culture conditions on nutrient components of Phaeophyta,Let us better grasp the characteristics of the growth of Phaeophyta.,through the relationship between environmental factors and nutritional components,it will provide a theoretical reference for artificial cultivation and acquisition..In this article,Sargassum thunbergii and Sargassum horneri were used as experimental subjects to compare growth rate,protein,ash,lipids,alginate,phlorotannin,fucoxanthin.(1)The Growth’s and Constituent Ingredinet’s Seasonal Variations of S.thunbergii on Different Tidal Zone in Rongcheng,ShandongSargassum thunbergii is a kind of usual brown algae on tidal zone which is rich in active ingredients such as alginate and fucoxathin,etc.The growth’s and constituent ingredinet’s seasonal variations of S.thunbergii on different tidal were studied.In this paper The growth of S.thunbergii was observed every 1-2 months;In March,June,October and December,collected the samples of S.thunbergii on tide zone and measure the length,biomass and component of S.thunbergii.It is showed that S.thunbergii grew fastest from May to July.The lengh and biomass of S.thunbergii growing on low tide zone were biggest.The protein and ash of S.thunbergii were high.The content of alginate ranged from 0.32-3.82%and reached its maximum on June;however the content of fucoxathin were lower significantly on June than on December and March.The content of polyphenol ranged from 0.32-3.82%and reached its maximum on March.Seasons have more effect on the contents of alginate,fucoxathin and polyphenol than the tidal zone have.The results provide a reference for exploiting these active ingredients from S.thunbergii.(2)Effects of different culture conditions on nutrient components of S.horneriWe studied the effects of different temperatures and light intensity on growth,photosynthetic pigment content and nutrient components in S.horneri.Temperature and light all had a significant effect on growth,photosynthetic pigment content,and nutrient components.The survival temperatures and light intensity for S.horneri were 5-20℃,50-300μmol/(m~2·s)respectively.The most suitable temperatures and light intensity were20℃,200-300μmol/(m~2·s)respectively,and specific growth rate reached higher.When the temperature was above 25℃,the blades would stop growing,become pale,and then rot.S.horneri could accumulate more photosynthetic pigment when the temperature was 25℃or the light intensity was at 50μmol/(m~2·s).There was no significant between different light intensity,soluble sugar and soluble protein was most at 10℃and 20℃.The highest ash and crude protein at 5-10℃or 50μmol/(m~2·s).Ether ectract was the fewest at 10℃or25℃,and there was no significant between different light intensity.S.horneri could accumulate more alginate when the temperature was 10℃or the illumination was at100μmol/(m~2·s).The highest fucoxanthin at 10℃or 50μmol/(m~2·s).Phlorotannin increases with the increase of light,at 200-300μmol/(m~2·s)reached the maximum,Low temperature(5℃)and high temperature(25℃)content increased.The results provide a theoretical basis for production and component extraction of S.horneri.(2)Effects of different drying methods on fucoxanthin content of S.horneri.To compare and analyze the effect of drying methods on the content of fucoxanthin in S.horneri,five different states of algae including natural state,the frozen state(-28℃),vacuum drying,freeze drying and hot air drying(40,60,80 and 120℃)were used todetermin and compare its effect on the content of fucoxanthin by colorimetry.The results showed that the drying state were in the following order:freeze drying,vacuum drying same as hot air drying 40℃,hot air drying 60℃,hot air drying 80℃,hot air drying120℃.The drying time from short to long:hot air drying,vacuum drying,frozen condition.The fucoxanthin content were in the following order from the highest to the lowest:natural state,frozen condition,hot air drying,freeze drying,vacuum drying,which was highest under the natural state,reaching1.957mg/g;while the lowest content of fucoxanthin was 0.367mg/g under 120℃hot air drying conditions,under different hot air drying temperature the fucoxanthin content were in the following order:40℃>60℃>80℃>120℃,significant difference.There was no significant difference between freeze drying,vacuum drying and hot air drying 40℃with P>0.05.Based on the above findings it was concluded that hot air drying under 40℃was an effective drying method for extracting fucoxanthinin S.horneri,which waslow-cost easy-operationand the fucoxanthin content was maintained at a higher level,so it is worth popularizing.